ARCHIEF
WILLIAM F. DURAND:
,,THE RESISTANCE AND
PROPULSION OF SHIPS"
2ND EDITION I 909.
tab.
v.
ScheepsbouwtcunJe
Techniscte Hog eschool
WILLIAM F. DURAND:
,,The Resistance and Propulsion of Ships."
2ND EDITION 1909.
The principal equations which we have to use:
Let w denote wake factor
prismatic, or cylindrical coefficient;
/3 ,, midship-section coefficient; L ,,
length in feet
p ,, - pitch ,, N Number of revolutiOnS.p1N1)' d
kim;. p1''100'
d 10'pN
l0I.3,u
1s1
= (I ± w)
(I-(1:-
w) .1-
=
(fLt/6
- .6) for single screw-ships;
(7)1 '.13
(jL76
- 1.1) for twin-screw ships;
(8)The values of k,. l,m, e2, and of 101.3 u may be taken from
Tables I, H, Ill,
IV, V for the values of slip, pitch-ratio,
area-ratio, and speed given, and b interpolationfor intermediatevalues.
Table I. Values of Factor k.
SL1P-RATI0.. k SLIP-RATIO. k ' SLIP-RATIO. k
.10 . A10 '.22' - .168: .32 .195 .12 .121 .24 .175 .34 .199 .14 . .132 ' .26 . .181 .36 .202 .16
:,
.142 .28 .186'.38
.204 .18 ;151 .30 .191 ' .40 .205'.20
.160.'
Table II. Values:of Factor 1.
PITCH-RATIO: SLIP-RATIO. 1.5 1.6 . 1.7 L8 . - 1.9 2.0 .524.465
..412.
368
.329 . .293 .12 .539 .481 430 384 .345 .311 .14 .550 . .493 .441 .397- - .359 - .325 .16 .560 .503 .452 .408 .369 ..336 .18 .569 .512. 46'1 .417379..
- .34520 :
-. 577 .521 .. .469 .426 .386 ..352
-.22, .24 -.584 . .590 - .528 . .478 .536' 44
.434 .441 .394 .401 .360 .366 .26 596 :542:,..491 .... 448:.
.. -'.406 .372 .28 : .600 .547 .496 454 .412 . .377 .30 .605 .551 - , .501 .458 .417 .381 .32 .609 .555. - .505. .462 .421 '- .385'34
.612 .558 .509:.466
.424 .389 .36 .614 .560. .512 .469 ' - :428 .392 38 615 562 514 471 430 - 394 .4Y.16
.563 .515 .472-432
-.396
SLIP-RATIO. .8 .9 .1.0 1.2 J.3 1.4 .10 1.35 1.15 1.00 .871 .763 .675 .594 .12 132 1.14 1.00 .875 .771 .682 -.610 .14 1.30 1.13 1.00 .879 .778 .691 .621 .16 1.29 1.13 1.00 .883 .784 .700 .630 .18 1.28 1.12 1.00- .886 .790 .707 .637 .20 1.28 1.12 1.00 - .889 .795 .714 .644 .22 1.28 1.12, 1.00. .891 .799 .719 .649 .24 1.28 1.1-2 1.0L -.89, .802 .724 .655 .26 1.28 1.12 1.00 .895 .806 727 .660 .28 1.27 1.12 1.00.897.
.809 .731. .66430
1.27 1.12 1.00 .899 .812 .734 .668 .32 1.27 1.12 1.00 .900 .816 .737 .670 .34 1.27 1.12 1.00 :. .818 .739 .673 .36 1.27 1.12 1.00 . .902 .81,9 .74165
.38 1.27 1.12 1.00 .903 .820 .742 .676 .40 1.26 1.12 1.00 .903 - 820 .742 .676Table 111
Values of Factor m.
PITCH-RATIO .8. PiTCH-RATIO .9. PITCH-RATIO 1:1. SLIP-RATIO. - AREA-RATIO.20
.30 .40 .50 .60 .1.0 ..595 .852 .1.00 1.07 1.12 20 715 8951.0
1.05 1.08:30
755 .919 1.00 1.04 1.07 40 .-784.930 -
1.00 1.04 1.06 PITCH1RATIO 1:2. SLIP-RATIO. AREA-RATIO...201.30
.40.60.
.10 .20 .575:go
.843.890 1.00.i.00
L08
I.06 . 1.13 1.09 -' .743 .912 I 00 105 1.07 .770 .925 1.00 1.04 1.07 AREA-RATIO. SLIP-RATIO. .20 .30 .40 .50 .60 :10 .660 883 i.00 1.06 1. .09 .2O .750 914 1.00 1.04 1.07 .30 .793 .930 1.00 1.03 1.05 .40 .820 .944. 1.00 1.02 1.03 PITCH-RATIO 1.0. SLIP-RATIO. AREA-RATIO.20.
.30 .40 .50 .60 .10 .620 865 1.00 Ir.io
.20 :725 .905 1.00 1.05 07 .30 .773 .927 1.00 1.04 1.06 .40 .802 .940 1.00 1.03 1.05 AREA-RATIO. SLIP-RATIO. .20 .30 .40 .50 .60 .10 .730 .900 I .00 .05 1.07 .20 .783 .927 1.00 1.04 1.06 .30 .819 .942 1.00 1.03 1.04. .40 .840 .950 1. .00 1.02 1.02PITCH-RATIO 1. AREA-RATIO. .20 .30 .40 .50 .60 .541 .813 1.00 1.10 1.15 .669
£73
1.00 1.07 1..I I .715 .892 1.00 1.06 1.09 .730 .902i.00
1.06 1.09 PITCH-RATIO 1.7. AREA-RATIO...20
.30 .40 .50 .60.540.
.812 1.00110
1.15.68
.873 1.00 1.07 1 .712 .895 LOU 1.06 1.09 .724 .901 LOU 1.06 1.09 PITCH-RATIO L3. AREA-RATIO. .20 .30 .40 .50 .60 .560 .831 1.00. ..i.09. 1.14 .680 .880 1.00 1.06 .11Q .732 .905 1.00 LOS 1.08 .755 919 1.00 1.05 1.08 PITCH-RATIO 1.4. AREA-RATIO. .20 .30 .40 .50 .60 .552 .823 i.oöI.09
1.14 .674£80
1.00 1.06 1.10 .726 .903 1.00 1.06 1.09 .744 .913 I 00 1.05 1.08 PiTCH-RATIO 1.5. AREA-RATIO .20 .30 .60 .549 .818 LOU 1.10 1.15 .670 .875 1.00 1.071.10
.720 .899 1.00 1.06 1.09 .736 .908 1.00 1.05 I .09PiTCH-RATIO 1.8. AREA-RATIO. SLIP-RATIO. .20 .30 .40 .50 .60 .10 .540 .813 1.00 1.10 1.16 .20 .669 .872 1.00 1.07 1.11 .30 .710 .892 1.00 1.06 1.10 .40 .719 .899 1.00 1.06 1.09 PITCH-RATIO 1.9. AREA-RATIO. SLIP-RATIO. .20 .30 .40 .50 .60 .10 .549 .815 1.00 1.11 1.16 .20 .670 .873 1.00 1.07 1.11 .30 .710 .891 1.00 -1.06 1.10 .40 .719 .899 1.00 1.06 1.09 PITCH-RATiO 2.0. AREA-RATIO. SLIP-RATIO. .20 .30 .40 .50 .60 .10 .556 .819 1.00 1.11 1.16 .20 .674 .873 1.00 1.07 1.12 .30 .711 .891 1.00 1.06 1.10 .40 .718 .899 1.00 1.06 1.09
.10 .20 .30 .40 SLIP-RATIO. .10 .20 .30 40 SLIP-RATIO. ..Io .20 30 .40 SLIP-RATIO. .10 .20 .30 .40
Table IV. Values of Efficiency.
PITCH-RATIO .8.. AREA-RATIO. .20 .30 .40 .0 .60 .58 6 I .63 '.63. .63 .64 .65 .66. . .66 .66 .62 .62 .63 .63 .63 .58 .58 .58 .58 .58 PITCH-RATIO .9. AREA-RATIO :20 . .30 .40 .50 .60 .57 .61 .64 .64 .63 .66 .67 .67 .67 .66 .64 .6 .64 .64 .64 .60 .59 .59' .58 .58 PITCH-RATIO .1.0. AREA-RATIO .30 .40 .30' .60" .57 .61 .64 .64 64 .67 :68 68 .68 '.67 .66 .66 .65 .64 .63,. .62 .61 .60 .58 .58 PITCH-RATIO 1.1. AREA-RATIO. .20 3Ø . .40 .50 .60 .56 .61 .64 .65 .65 .69 .69 .69 .68 .68 .68 .67 .66 .65 .64 .64 .62 .60 .5g 58 PITCH-RATIO 1.2. AREA-RATIO .20 .30 .40 .50 .60 .56 .61 .64 .65' .64' 70 .70 .69 .69 .69 .70 .68 .68 .66 .65 .65 63 .62 .60 39
PITCH-RATIOT L3. PITCH-RATIO 1.7. 7. SLIP-RATIO. AREA-RATIO. .20 .30 .40 .50 .60 .10 . 54 ' .60 .64 .65 .66 .20 ' .72 .72 .72 .71 .70 .30 .72 .72 .71 .69 .68 .40 .68 .67 .65 .64 .63 SUP-RATIO. AREA-RATIO. .20 . .30 40 .50 .60
;i0
: 61 .64 .65 .65 .20 71 ;71 .70 :".70 .69 3O :71.70.
.69 67 .65 ?40 .66 .65 .64 .61' 60 PITCH-RATIO' 1.4. SLIP-RATIO. 'AREA-RATIO. 20 .30 .40 .50 .60.IO
:52 F ...60 ....63 .64. .64 .20 71 .'.73
.73.
.72 .72 .30 '.72 .73 72 .71 .70 :40 .68 .68 .67 65 .65PITCH-RArIO 1.5.
SLIP-RATIO.AR-RATIO
.20'.30
.40 .50 .60y10
.60 .64 .65 .66 .71 .72 ..71 .70 .70 :30 :.72 .71 .69 .68 .66 .40 .67 .65 .64 .62 .61 PITCH-RATIO 1.6. SLIP-RATIO. AREA-RA'fIO. .20 F .30 40 , .50 .60.10
.54 .60 .64 .65 .66 .20 .72 .7212
.71 .70 .30 .73 .72 .70 .68 .68 .40 .68 .66' .64 .63 .628 PITC I-I-RATIO 1.8. AREA-RATIO. SLIP-RATIO. .20 !30 .40 .50 .60 '.10 .53 .60 .64 .65 .65 .20 .72 .73 .73 .72 .71 .30 .73 .73 .71 .70 .69 AU .69 .67 66 .64 PITCH-RATIO 1.9. SLIP-RATIO. AREA-RATIO. .20 .30